Multi-purpose copolymers derived from, for example, the dimethylaminoethyl methacrylate (DMAEMA) monomer are known in the art. Such copolymers when produced from the afore-mentioned monomer can, in certain applications, have stability issue. As a result, such polymers have a poor shelf life and can start to “destabilize” after about six months. This in turn causes various logistic problems and undesirable performance degradation. The poor shelf life of these polymers is due to the amine backbone contained in the DMAEMA monomer which readily undergoes hydrolysis in an aqueous medium through “back-biting”. The lone-pair electron on the nitrogen atom attacks the electron deficient carbonyl carbon to yield a five member ring Zwitterionic intermediate. Such a structure can then be easily hydrolyzed in the presence of water. The reaction scheme shown below summarizes the problem associated with copolymers that are derived from a DMAEMA monomer. As a result of the hydrolysis —COOH functional sites are produced on the backbone of a copolymer, as well as a dimethylaminoethanol by-product.

Given the above, there is a need in the art for hydrolytically stable multi-purpose copolymers that possess a suitable shelf life (e.g., in excess of six months or more).